At present, in order to have vivid color performance, most video-display systems support adjustment methods for input color signals in a RGB (Red, Green, Blue) format, in a YCbCr (Luminance, B Chrominance, R Chrominance) format, or in an HIS (Hue, Intensity, Saturation) format. The color signal in an HIS format differentiates among the corresponding meanings of set values of H, I, and S by a coordinate method. The H represents a hue-coordinate. It is like angle-coordinate in a cylindrical coordinate system. Besides, it is periodic. Thereby, it is only necessary to set a corresponding color for an angle of circumference. The hue-coordinate, like the angle-coordinate, is divided into 360 degrees. Roughly speaking, the colors start gradually from red (the visible light with the longest wavelength) to purple (the visible light with the shortest wavelength), then return to red. The I (intensity-coordinate) and the S (saturation-coordinate) both are divided into 100 parts, and are represented by percentage. They are like the r-coordinate (radius-coordinate) and the z-coordinate (height-coordinate) in a cylindrical coordinate system; thereby I and S can be represented by using a planar orthogonal coordinate system.
Currently, most video-display systems adopt the formats described above, and manually adjust detailed associated values of colors to present preferred appearance of frames. However, in natural images, possibly due to complex background colors, adjusted colors still cannot perform strongly the desired presentation of frames. Alternatively, because when adjusting values of a single color, color-, intensity-, and saturation-coordinates of other colors will be affected, thereby colors will distort. Consequently, users' visual demands cannot be satisfied.
Accordingly, the present invention provides a color adjustment apparatus and a method thereof. Not only the drawback of monotonous and non-vivid colors in played frames can be improved, but also the presentation of other color will not be affected when adjusting colors. Thereby, users' visual experience can be enhanced significantly.